Fabrication of integrated copper indium diselenide nanorod arrays on silicon using porous anodic alumina as template

Vertically aligned copper indium diselenide nanorod arrays were synthesized by electrodeposition using porous anodic alumina template supported on a tungsten/silicon substrate. Porous anodic alumina template was fabricated by anodizing aluminium film which was sputtered onto tungsten/silicon substrate. The approach employed a selective chemical etching to penetrate the barrier layer at the bottom of alumina pore before electrodeposition. It enables direct electrical and chemical contact with the underside substrate electrode. The as-deposited sample was annealed at 450°C in vacuum. High resolution transmission electron microscopy and X-ray diffraction showed high purity CuInSe₂ nanorods with a preferred [112] orientation. Scanning electron microscopy revealed that the nanorods were dense and compact with diameter about 100 nm and with length approximate 1000 nm. Energy-dispersive X-ray spectroscopy showed fabrication of nearly close to stoichiometric CuInSe₂. The energy band gap of this nonorod arrays was analysed by fundamental absorption spectrum and evaluated to be 1.06 eV.